RF Phase Shifter Using Coupled Microstrip Square Rings Tunable Bandpass Filter

This paper presents a study, optimization and simulation of tunable bandpass filter centered at 2.4GHz and used as phase shifter based on coupled microstrip square ring loaded by varactor diodes. We have performed an electromagnetic simulation on Momentum software of ADSTM; we have used the power of the Momentum software for the optimization and simulation of our circuit. A good results were obtained; the filter results in an insertion loss of 0.35 dB−0.26 dB over tuning range and 3−dB b andwidth o f 3 00MHz−360MHz. W e c ompute a f ractional bandwidth between 13% and 14.5% for our circuit and for different value of capacitance. We compute also a good dynamic range of phase shifting about 90° at operating frequency 2.4GHz for different value of capacitance.